Question

Please help with the question on the screen ( 41)

Answer 1

The half life of a nuclear element tells us the time it takes for a radioative material to reduce to half its value.

If the Initial amount is A_0,

then after 1 half life, remaining = 1/2 A_0

then after 2 half life, remaining = (1/2) 1/2 A_0 = 1/4 A_0

...

The half life equation is

`A_t=A_0((1)/(2^n)^{})`

A_0 is initial amount

n is the number of half lives that pass in interval "t"

A_t is the undecayed amount after time interval "t"

a)

Given half life is 138 days and

138 * 6 = 828 days

So,

6 half lives occur in 828 days

b)

The amount of Polonium in the sample is >>>>

`\begin{gathered} A_t=A_0((1)/(2^n)^{}) \\ A_t=60((1)/(2^6)) \\ A_t=0.9375 \end{gathered}`

Rounded, that 0.94 grams

Correct Answer

A